Seadragon is technology, which allows you to create applications capable of displaying unlimited size images in users (small) display. It works similar to Google Maps, where you move (zoom) closer and closer to the ground and see more and more details. When I first saw it (video available here) I couldn't believe my yes - how it is possible to scale so many pixels in one screen? Lets find out.

There are multiple implementations of Seadragon: Ajax or Silverlight based, mobile version and maybe more. All of them works the same - loads only that part of image which is now visible. What you need to do as developer is to create collection of images parts which will later be used to create zoom effect